Bridge with minimized excited bridge vibrations

ABSTRACT

The invention includes a bridge with a structure having at least one excited bridge frequency. The bridge includes a plurality of vibration absorber disposed in the bridge. The excited bridge vibration absorbers include tuning masses pivotally connected to support frames for pivotal movement relative to pivotal axis&#39;s and torsional springs disposed along said pivotal axis. The torsional spring provide a spring forces responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein said the bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs the excited bridge frequency.

CROSS REFERENCE

This application claims the benefit of, and incorporates by reference, U.S. Provisional Patent Application No. 60/704,409 filed on Aug. 1, 2005.

FIELD OF THE INVENTION

The present invention relates to bridges with minimized excited bridge vibrations and a method/system for absorbing vibrations. More particularly the invention relates to a method of controlling vibrations in a bridge having an excited bridge frequency and a bridge vibration control system for absorbing vibrations.

BACKGROUND OF THE INVENTION

There is a need for bridges with minimized excited bridge vibrations. There is a need for bridges with minimal vibrations and a method of accurately and economically absorbing excited bridge vibrations to minimize vibrations in bridges. There is a need for an economically feasible method of absorbing excited bridge vibrations. There is a need for a robust bridge system and method of making excited bridge vibration absorbers. There is a need for an economic excited bridge vibration absorber and method for absorbing excited bridge vibrations.

SUMMARY OF THE INVENTION

The invention includes a bridge. The bridge includes a structure having at least one excited bridge frequency. The bridge structure having a bottom plate and a top plate and a bridge interior conduit chamber. The bridge includes a first bridge pivoting vibration absorber disposed in the bridge interior conduit chamber, the first bridge pivoting vibration absorber including a first bridge pivoting vibration absorber planar support frame with a first bridge pivoting vibration absorber foundation planar plate surface, the first bridge pivoting vibration absorber foundation planar plate surface abutting the top plate with the first bridge pivoting vibration absorber planar support frame attached to the top plate. The first bridge pivoting vibration absorber includes a tuning mass pivotally connected to the first bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis. The first bridge pivoting vibration absorber includes a spring disposed along the pivotal axis between the support frame and the tuning mass providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the first bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency. The bridge preferably includes a second bridge pivoting vibration absorber disposed in the bridge interior conduit chamber, the second bridge pivoting vibration absorber including a second bridge pivoting vibration absorber planar support frame with a second bridge pivoting vibration absorber foundation planar plate surface, the second bridge pivoting vibration absorber foundation planar plate surface abutting the bottom plate, the second bridge pivoting vibration absorber planar support frame attached to the bottom plate, a tuning mass pivotally connected to the second bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a spring disposed along the pivotal axis between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the second bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency.

The invention includes a method of controlling vibrations in a bridge having an excited bridge frequency. The method includes the step of providing a first bridge vibration absorber, the first bridge vibration absorber including a first bridge vibration absorber planar support frame, a tuning mass connected to the first bridge vibration absorber planar support frame for movement relative to an axis, a spring disposed along the axis and between the support frame and the tuning mass, the spring providing a spring force responsive to a movement of the tuning mass about the axis relative to the support frame wherein the first bridge vibration absorber has a natural resonant frequency below 1.5 Hz. The method includes attaching the first bridge vibration absorber planar support frame to the bridge, wherein the first bridge vibration absorber natural resonant frequency absorbs the excited bridge frequency.

The invention includes a bridge vibration absorber for absorbing a problematic excited bridge frequency of a bridge. The bridge vibration absorber includes a bridge vibration absorber planar support frame. The bridge vibration absorber includes a bridge vibration absorber tuning mass connected to the bridge vibration absorber planar support frame for movement relative to an axis. The bridge vibration absorber includes a bridge vibration absorber spring disposed along the axis and between the support frame and the tuning mass, the spring providing a spring force responsive to a movement of the tuning mass about the axis relative to the support frame wherein the bridge vibration absorber planar support frame provides for attachment of the bridge vibration absorber to the bridge with the bridge vibration absorber having a natural resonant frequency below 1.5 Hz.

The invention includes a method of making a vibration absorber for a structure having a problematic excited frequency. The method includes providing a pivoting vibration absorber planar support frame plate, the pivoting vibration absorber planar support frame plate for attachment to the structure. The method includes providing a tuning mass and pivotally connecting the tuning mass to the pivoting vibration absorber planar support frame plate for pivotal movement relative to a pivotal axis. The method includes providing a torsional spring and disposing the torsional spring along the pivotal axis between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs the excited frequency.

The invention includes a tuned vibration absorber for absorbing vibratory disturbances in a structure, the tuned vibration absorber including a vibration absorber planar support frame plate for attachment to the structure. The tuned vibration absorber includes a tuning mass movably connected to the support frame plate for movement relative to a pivotal axis. The tuning mass preferably includes an arm and an adjustment mass located along the length of the arm with the tuning mass suspended away from the planar support frame plate. The tuned vibration absorber includes a torsional spring located along the pivotal axis and positioned between the adjustment mass and the support frame plate and wherein the torsional spring provides a spring force responsive to pivotal rotation of the tuning mass about the pivotal axis relative to the support frame plate.

The invention includes a method of making a vibration absorber for a structure having a problematic excited frequency. The method includes providing a pivoting vibration absorber support frame, the pivoting vibration absorber support frame for attachment to said structure, providing a tuning mass arm and pivotally connecting the tuning mass arm to the pivoting vibration absorber support frame for pivotal movement relative to a pivotal axis, providing a first torsional spring member and at least a second torsional spring member and disposing the first torsional spring member and the second torsional spring member in series along the pivotal axis between the support frame and the tuning mass arm, the first torsional spring member and the at least second torsional spring member in series providing a torsional spring force responsive to a pivotal rotation of the tuning mass arm about the pivotal axis relative to the support frame wherein the pivoting vibration absorber has a low natural resonant frequency which absorbs the excited frequency.

It is to be understood that both the foregoing general description and the following detailed description are exemplary of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the invention, and together with the description serve to explain the principals and operation of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a bridge with an excited bridge frequency and bridge vibration absorbers.

FIG. 2 shows a bridge structure with bridge vibration absorbers.

FIG. 3 shows a bridge structure with bridge vibration absorbers.

FIG. 4 shows a view of a bridge vibration absorber.

FIG. 5 shows a view of a bridge vibration absorber.

FIG. 6 shows a view of a bridge vibration absorber.

FIG. 7 shows a view of a bridge vibration absorber.

FIG. 8 shows a view of a bridge vibration absorber spring.

FIG. 9 shows a view of a bridge vibration absorber spring.

FIG. 10 shows views of bridge vibration absorber tuning mass weight members.

FIG. 11 shows a view of a bridge vibration absorber with the tuning mass weight members removed.

FIG. 12 shows a view of a bridge vibration absorber with the tuning mass weight members removed.

FIG. 13 shows a view of a bridge vibration absorber with the tuning mass weight members removed.

FIG. 14 shows a view of a bridge vibration absorber with the tuning mass weight members removed.

FIG. 15 shows a view of a bridge vibration absorber support frame.

FIG. 16A shows a view of a bridge vibration absorber support frame.

FIG. 16B shows a view of a bridge vibration absorber support frame.

FIG. 16C shows a view of a bridge vibration absorber support frame.

FIG. 17A shows a view of a bridge vibration absorber.

FIG. 17B shows a view of a bridge vibration absorber.

FIG. 18A shows a view of a bridge vibration absorber.

FIG. 18B shows a view of a bridge vibration absorber.

FIG. 18C shows a view of a bridge vibration absorber.

FIG. 18D shows a cut out view of the bridge vibration absorber arm.

FIG. 19A shows a bridge with excited bridge frequencies and bridge vibration absorbers.

FIG. 19B shows the bridge structure with bridge vibration absorbers.

FIG. 19C shows the bridge structure with bridge vibration absorbers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.

The invention includes a tuned vibration minimized bridge. The bridge includes a structure having at least one excited bridge frequency. The bridge structure having a bottom plate and a top plate and a bridge interior conduit chamber. The bridge includes a first bridge pivoting vibration absorber disposed in the bridge interior conduit chamber, the first bridge pivoting vibration absorber including a first bridge pivoting vibration absorber planar support frame with a first bridge pivoting vibration absorber foundation planar plate surface, the first bridge pivoting vibration absorber foundation planar plate surface abutting the top plate with the first bridge pivoting vibration absorber planar support frame attached to the top plate. The first bridge pivoting vibration absorber includes a tuning mass pivotally connected to the first bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis. The first bridge pivoting vibration absorber includes a spring disposed along the pivotal axis between the support frame and the tuning mass providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the first bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency. The bridge preferably includes a second bridge pivoting vibration absorber disposed in the bridge interior conduit chamber, the second bridge pivoting vibration absorber including a second bridge pivoting vibration absorber planar support frame with a second bridge pivoting vibration absorber foundation planar plate surface, the second bridge pivoting vibration absorber foundation planar plate surface abutting the bottom plate, the second bridge pivoting vibration absorber planar support frame attached to the bottom plate, a tuning mass pivotally connected to the second bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a spring disposed along the pivotal axis between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the second bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency.

A tuned vibration minimized bridge 20 is shown in FIG. 1. Preferably the bridge 20 is a nonsuspension bridge, preferably with the bridge bottom supported. Preferably the bridge 20 is comprised of a box girder structure 22 having at least one excited bridge frequency 24. Preferably the bridge structure 22 has a bottom plate 26 and a top plate 28. Preferably the bridge box girder structure 22 includes a first side plate 30 and a second side plate 32 with the bottom plate 26 and the top plate 28 forming a bridge interior conduit chamber 34. Preferably the bridge structure plates have interior planar surfaces 36. The bridge 20 includes a first bridge pivoting vibration absorber 40 disposed in the bridge interior conduit chamber 34. The first bridge pivoting vibration absorber 40 includes a first bridge pivoting vibration absorber planar support frame 42 with a first bridge pivoting vibration absorber foundation planar plate surface 44. Preferably the first bridge pivoting vibration absorber foundation planar plate surface 44 is abutting the top plate 28 and the planar surface 36 with the first bridge pivoting vibration absorber planar support frame 42 attached to the top plate 28, preferably with attachment members 48 such as threaded bolt members. The first bridge pivoting vibration absorber 40 includes a tuning mass 50 pivotally connected to the first bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52. The first bridge pivoting vibration absorber 40 includes a torsional spring 54 disposed along the pivotal axis 52 between the support frame 42 and the tuning mass 50. In a preferred embodiment the torsional spring member 54 is comprised of a first spring member and at least a second spring member in series. In a preferred embodiment the torsional spring 54 is comprised of an elastomer 56. In a preferred embodiment the torsional spring 54 is comprised of at least a first torsional spring elastomer member. In a preferred embodiment the torsional spring 54 is comprised of at least a first spring coil 59. In a preferred embodiment the torsional spring 54 is comprised of a spring coil 59 and an elastomer 56, preferably with the elastomer spring 56 and coil spring 59 in series, preferably with the coil spring proximate to and attached to the pivot arm 64 and the elastomer spring attached to the other distal end of the coil spring and the frame. As shown in FIG. 17A-B, preferably the coil 59 and elastomer spring 55 are used in series along the pivotal axis, preferably with the coil spring first end connected with the first rigid plate member 57 of elastomeric torsional spring member 55 which is bonded to center elastomer 56 which is bonded to second rigid plate member 57 which is anchored to the frame about axis 52. Preferably the second end of the coil is connected with the arm 64. The torsional spring 54 provides a spring force responsive to a pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame 42 wherein the first bridge pivoting vibration absorber 40 has a low natural resonant frequency 58, 58′, 58″ below 1.5 Hz which absorbs an excited bridge frequency 24. Preferably the first bridge pivoting vibration absorber 40 low natural resonant frequency 58, 58′, 58″ is less than 1.375 Hz which absorbs an excited bridge frequency 24, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the method of making the vibration absorber for the structure having the problematic excited frequency includes providing a pivoting vibration absorber support frame plate, the pivoting vibration absorber planar support frame plate for attachment to the structure. The method includes providing the tuning mass arm and pivotally connecting the tuning mass arm to the pivoting vibration absorber support frame for pivotal movement relative to a pivotal axis. The method includes providing a first torsional spring member and at least a second torsional spring member and disposing the first torsional spring member and the second torsional spring member in series along the pivotal axis between the support frame and the tuning mass arm. The first torsional spring member and the at least second torsional spring member in series providing a torsional spring force responsive to the pivotal rotation of the tuning mass arm about the pivotal axis relative to the support frame wherein the in series spring pivoting vibration absorber having a low natural resonant frequency 58, 58′, 58″ below 1.5 Hz which absorbs the excited structure problematic frequency. In a preferred embodiment the in series first and at least second spring members includes coil 59 and elastomer 56. In a preferred embodiment the in series first and at least second spring members includes first elastomer 56 and at least second elastomer 56. In a preferred embodiment the in series first and at least second spring members includes first elastomer 56, second elastomer 56, and third elastomer 56.

The bridge 20 includes a second bridge pivoting vibration absorber 60 disposed in the bridge interior conduit chamber 34. The second bridge pivoting vibration absorber 60 including a second bridge pivoting vibration absorber planar support frame 42 with a second bridge pivoting vibration absorber foundation planar plate surface 44, with the second bridge pivoting vibration absorber foundation planar plate surface 44 abutting the bottom plate 26, with the second bridge pivoting vibration absorber planar support frame attached to the bottom plate 26. Preferably the second bridge pivoting vibration absorber planar support frame 42 is securely attached and bolted to the bottom plate 26 with the second bridge pivoting vibration absorber foundation planar plate surface 44 flush against the bottom plate planar surface 36. The second bridge pivoting vibration absorber 60 includes a tuning mass 50 pivotally connected to the second bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52. The second bridge pivoting vibration absorber 60 includes a torsional spring 54, preferably including at least one elastomer torsional spring. The torsional spring 54 is disposed along the pivotal axis 52 between the support frame 42 and the tuning mass 50, with the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame wherein the second bridge pivoting vibration absorber has a natural resonant frequency 58 below 1.5 Hz which absorbs an excited bridge frequency 24. Preferably the second bridge pivoting vibration absorber 60 natural resonant frequency 58 <1.375 Hz which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz.

Preferably the nonsuspension bridge 20 is cable free in that it is not suspended by cables, preferably with the bridge structure girder supported by an underneath foundation system and not hung from above by a cable system. Preferably the girder bridge 20 bridges a geographic depression such as a river or valley. Preferably the box girder beam structure 22 provides a bridge interior conduit chamber 34 across the geographic depression.

Preferably the bridge 20 includes a third bridge vibration absorber disposed in the bridge interior conduit chamber, the third bridge vibration absorber including a third bridge vibration absorber planar support frame 42 with a third bridge vibration absorber foundation planar plate surface 44, the third bridge vibration absorber foundation planar plate surface preferably abutting the top plate 28, the third bridge vibration absorber planar support frame 42 attached to the top plate 28. Preferably the third bridge vibration absorber includes a tuning mass 50 pivotally connected to the third bridge vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52 and a torsional spring 54 disposed along the pivotal axis between the support frame and the tuning mass. The torsional spring 54 provides a spring force responsive to a pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame 42 wherein the third bridge pivoting vibration absorber has a natural resonant frequency below which absorbs an excited bridge frequency 24. Preferably the third bridge pivoting vibration absorber natural resonant frequency 58 is <1.375 Hz and which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz.

Preferably the bridge 20 includes a fourth bridge vibration absorber disposed in the bridge interior conduit chamber, the fourth bridge vibration absorber including a fourth bridge vibration absorber planar support frame 42 with a fourth bridge vibration absorber foundation planar plate surface 44. The fourth bridge vibration absorber foundation planar plate surface 44 abuts the bottom plate planar surface 36, with the fourth bridge pivoting absorber planar support frame attached to the bottom plate 26. The fourth bridge vibration absorber includes a tuning mass 50 pivotally connected to the fourth bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52. The fourth bridge vibration absorber includes a torsional spring 54 disposed along the pivotal axis 52 between the support frame and the tuning mass, with the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame wherein the fourth bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency 24. Preferably the fourth bridge pivoting vibration absorber natural resonant frequency 58 is <1.375 Hz which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz.

Preferably the torsional springs 54 are comprised of at least three elastomeric torsional spring members 55 in series. Preferably the elastomeric torsional spring members 55 are comprised of an elastomer 56. As shown in FIG. 3, 4, 6, 7, 11, 12, 14, three elastomeric torsional spring members 55 are preferably utilized in series. As shown in FIG. 8-9 the elastomeric torsional spring members 55 are preferably comprised of a center elastomer 56 bonded between two rigid plate members 57. The elastomeric torsional spring members 55 are preferably utilized in series by fixing the adjacent rigid plate members of three spring members together, preferably such as shown in FIG. 3, 4, 6, 7, 11, 12, 14. The in series elastomeric torsional spring members 55 work in series between the support frame 42 and the tuning mass 50. In a preferred embodiment the torsional spring 54 is comprised of a spring coil 59. In a preferred embodiment the torsional spring 54 is comprised of a spring coil 59. In a preferred embodiment the torsional spring 54 is comprised of a spring coil 59 and an elastomer 56, preferably with the elastomer spring 56 and coil spring 59 in series, preferably with the coiled spring proximate to and attached to the pivot arm 64 and the elastomer spring attached to the other distal end of the coil spring and the frame. As shown in FIG. 17A-B, preferably the coil 59 and elastomer spring 55 are used in series along the pivotal axis, preferably with the coil spring first end connected with the first rigid plate member 57 of elastomeric torsional spring member 55 which is bonded to center elastomer 56 which is bonded to second rigid plate member 57 which is anchored to the frame about axis 52. Preferably the second end of the coil is connected with the arm 64. Preferably the spring coil 59 is contained within a coil spring enclosure 61, preferably with a first coil enclosure 61 housing the first end of the coil attached to the elastomer spring rigid plate 57 and a second coil enclosure 61 housing the second end of the spring coil 59 attached to the arm 64. The elastomeric torsional spring member 55 and coil spring 59 are preferably utilized in series by fixing the spring ends together, preferably such as with rigid plate 57, with the in series elastomeric torsional spring member and the coil torsional spring member working in series between the support frame 42 and the tuning mass 50 placed on arm 64.

The invention includes a method of controlling vibrations in a bridge having an excited bridge frequency. The method includes the step of providing a first bridge vibration absorber, the first bridge vibration absorber including a first bridge vibration absorber planar support frame, a tuning mass connected to the first bridge vibration absorber planar support frame for movement relative to an axis, a spring disposed along the axis and between the support frame and the tuning mass, the spring providing a spring force responsive to a movement of the tuning mass about the axis relative to the support frame wherein the first bridge vibration absorber has a natural resonant frequency below 1.5 Hz. The method includes attaching the first bridge vibration absorber planar support frame to the bridge, wherein the first bridge vibration absorber natural resonant frequency absorbs the excited bridge frequency.

The invention includes a method of controlling vibrations in bridge 20 having an excited bridge frequency 24. The method includes providing the first bridge pivoting vibration absorber 40. The first bridge vibration absorber 40 includes first bridge vibration absorber planar support frame 42, tuning mass 50 pivotally connected to the first bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52. The first bridge vibration absorber 40 includes torsional spring 54 disposed along the pivotal axis and between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation movement of the tuning mass 50 about the pivotal axis 52 relative to the support frame 42 wherein the first bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz. The method includes attaching the first bridge vibration absorber planar support frame 42 to the bridge 20, wherein the first bridge pivoting vibration absorber natural resonant frequency 58, 58′, 58″ absorbs the excited bridge frequency 24. Preferably the bridge includes a girder structure 22, preferably including a structural plate with an interior planar surface 36. Preferably the box girder structure 22 forms a bridge interior conduit chamber 34. Preferably the first bridge pivoting vibration absorber 40 has a natural resonant frequency <1.375 Hz which absorbs the excited bridge frequency 24, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the method includes providing a second bridge pivoting vibration absorber 60. The second bridge vibration absorber 60 includes a second bridge vibration absorber planar support frame 42, a tuning mass 50 pivotally connected to the second bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to pivotal axis 52. The second bridge vibration absorber 60 includes a torsional spring 54 disposed along the pivotal axis 52 and between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation movement of the tuning mass about the pivotal axis relative to the support frame wherein the second bridge pivoting vibration absorber has a low natural resonant frequency below 1.5 Hz. The method includes attaching the second bridge vibration absorber planar support frame 42 to the bridge 20 at a second placement point distal from the first bridge pivoting vibration absorber, wherein the second bridge pivoting vibration absorber natural resonant frequency absorbs excited bridge frequency 24. Preferably the second bridge pivoting vibration absorber 60 natural resonant frequency <1.375 Hz which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the first bridge pivoting vibration absorber 40 is attached to a top plate 28 inside surface 36 of box girder bridge interior conduit chamber 34. Preferably the second bridge vibration absorber 60 is attached to a bottom plate inside surface 36 of box girder bridge interior conduit chamber 34. Preferably a plurality of pivoting vibration absorbers are attached to a bridge structure 22 along a longitudinal span length of the bridge. Preferably the bridge 20 is a nonsuspension bridge 20. Preferably the bridge 20 is a nonsuspension bridge that is cable free in that it is not suspended by cables. Preferably with the bridge structure girder 22 is supported by an underneath foundation system and not hung from above such as by a suspension cable system. Preferably the girder bridge 20 bridges a geographic depression such as a river or valley. Preferably the box girder beam structure 22 provides a bridge interior conduit chamber 34 across the geographic depression. Preferably the method includes providing a third bridge vibration absorber. Preferably the bridge vibration absorber is disposed in the bridge interior conduit chamber 34. Preferably the third bridge vibration absorber includes a third bridge vibration absorber planar support frame 42 with a third bridge vibration absorber foundation planar plate surface 44. Preferably the third bridge vibration absorber includes tuning mass 50 pivotally connected to the third bridge vibration absorber planar support frame 42 for pivotal movement relative to pivotal axis 52. Preferably the third bridge vibration absorber includes a torsional spring 54 disposed along the pivotal axis 52 between the support frame 42 and the tuning mass 50, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the third bridge pivoting vibration absorber has a natural resonant frequency 58 below 1.5 Hz which absorbs an excited bridge frequency 24. The method includes attaching the third bridge vibration absorber to the bridge at a third placement point. Preferably the third bridge pivoting vibration absorber natural resonant frequency is <1.375 Hz and which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the method includes providing a fourth bridge vibration absorber. The fourth bridge vibration absorber includes a fourth bridge vibration absorber planar support frame 42 with a fourth bridge vibration absorber foundation planar plate surface 44. The fourth bridge vibration absorber includes a tuning mass 50 pivotally connected to the fourth bridge pivoting vibration absorber planar support frame for pivotal movement relative to pivotal axis 52. The fourth bridge vibration absorber includes a torsional spring 54 disposed along the pivotal axis 52 between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the fourth bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz) which absorbs an excited bridge frequency 24. The method includes attaching the fourth bridge vibration absorber to the bridge 20 at a fourth placement point. Preferably the fourth bridge pivoting vibration absorber natural resonant frequency is low and <1.375 Hz which absorbs the excited bridge frequency, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the method includes lowering the frequency of the natural resonant frequency below 1.5 Hz for the bridge 20. Preferably the method includes lowering the frequency of the natural resonant frequency below 1.375 Hz, preferably <1.2 Hz, preferably <1.1 Hz, and preferably <0.5 Hz. Preferably the natural resonant frequency 58, 58′, 58″ is lowered in the field at the location of the bride 20 by adding more weights 62 to the tuning mass 50. Preferably the tuning mass 50 has a tuning mass amount ≧90 lbs, preferably ≧91 lbs. Preferably the tuning mass 50 has a tuning mass amount ≧100 lbs, preferably ≧101 lbs. As shown in FIG. 2, 4, 5, 6, 10 tuning mass preferably is comprised of tuning mass weight plate members 62. As shown in the preferred embodiments in the tuning mass weight plate members 62 are 15 lb weight plates. Preferably the method includes lowering the frequency of the natural resonant frequency 58, 58′, 58″ below 1.5 Hz for the bridge 20 by moving the tuning mass weight plate members 62 further out on the pivotal arm 64 and away from the pivotal axis 52. Preferably the tuning mass pivotal arm 64 has a longitudinal channel with the tuning mass weight plate members 62 movably positional along the longitudinal length of arm 64 and secured along the length of the arm such as with bolts. Preferably the spring 54 is comprised of at least a first elastomeric torsional spring member 55 in series with a second spring member. Preferably the spring 54 is comprised of at least three elastomeric torsional spring member 55 in series, with elastomer 56 sandwiched between rigid plates 57, with adjacent plates 57 attached together to work in series. Preferably the method of controlling vibrations in bridge 20 includes making the vibration absorber for the bridge structure having a problematic excited frequency, including providing a pivoting vibration absorber support frame, the pivoting vibration absorber support frame for attachment to the structure, providing a tuning mass arm and pivotally connecting the tuning mass arm to the pivoting vibration absorber support frame for pivotal movement relative to a pivotal axis, providing a first torsional spring member and at least a second torsional spring member and disposing the first torsional spring member and the second torsional spring member in series along the pivotal axis between the support frame and the tuning mass arm, the first torsional spring member and the at least second torsional spring member in series providing a torsional spring force responsive to a pivotal rotation of the tuning mass arm about the pivotal axis relative to the support frame wherein the pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs the excited bridge structure frequency. In a preferred embodiment the invention includes utilizing the bridge vibration absorbers that include a coil 59, preferably a torsional coil spring 59 in series with an elastomeric torsional spring member 55, In a preferred embodiment the invention includes utilizing first bridge vibration absorbers with in series coils 59 and elastomers 56 and tuning masses 50 on arms 64 having a natural resonant frequency 58″ at a first bridge longitudinal middle span location and second bridge vibration absorbers with in series plurality of at least first and second elastomers 56 and tuning masses 50 on arms 64 having a natural resonant frequency 58′ at a second distal bridge longitudinal span location. In an embodiment such as shown in FIG. 19A-C, the invention preferably includes utilizing first bridge vibration absorbers with in series coils 59 and elastomers 56 and tuning masses 50 on arms 64 having a natural resonant frequency 58″ at a first bridge longitudinal middle span location and second bridge vibration absorbers with in series plurality of at least first and second elastomers 56 and tuning masses 50 on arms 64 having a natural resonant frequency 58′ at a second distal bridge longitudinal side span location with 58″<58′.

The invention includes a bridge vibration absorber for absorbing a problematic excited bridge frequency of a bridge. The bridge vibration absorber includes a bridge vibration absorber planar support frame. The bridge vibration absorber includes a bridge vibration absorber tuning mass connected to the bridge vibration absorber planar support frame for movement relative to an axis. The bridge vibration absorber includes a bridge vibration absorber spring disposed along the axis and between the support frame and the tuning mass, the spring providing a spring force responsive to a movement of the tuning mass about the axis relative to the support frame wherein the bridge vibration absorber planar support frame provides for attachment of the bridge vibration absorber to the bridge with the bridge vibration absorber having a low natural resonant frequency below 1.5 Hz.

The bridge pivoting vibration absorber for absorbing a problematic excited bridge frequency of a nonsuspension bridge includes a bridge vibration absorber planar support frame 42, a tuning mass 50 pivotally connected to the bridge pivoting vibration absorber planar support frame 42 for pivotal movement relative to a pivotal axis 52, a torsional spring 54 disposed along the pivotal axis and between the support frame and the tuning mass, with the torsional spring 54 providing a spring force responsive to a pivotal rotation movement of the tuning mass 50 about the pivotal axis 52 relative to the support frame 42 wherein the bridge pivoting vibration absorber planar support frame 42 provides for attachment of the bridge pivoting vibration absorber to the bridge 20 with the bridge pivoting vibration absorber having a natural resonant frequency 58 below 1.5 Hz. Preferably the bridge pivoting vibration absorber natural resonant frequency 58 is <1.375 Hz and which absorbs the excited bridge frequency 24, preferably with the natural resonant frequency <1.2 Hz, preferably <1.1 Hz, preferably <0.5 Hz. Preferably the bridge pivoting vibration absorber is a girder bridge vibration absorber for minimizing nonsuspension bridge excited bridge frequencies. Preferably the bridge pivoting vibration absorber is a cable free bridge girder vibration absorber for minimizing nonsuspension bridges supported by an underneath foundation system and not hung from above by a cable suspension system, preferably for a girder bridge 20 over a geographic depression such as a river and/or valley. Preferably the bridge vibration absorber planar support frame 42 is matched to planarly abut and flush mount to a planar structural plate surface 36 of the bridge 20, preferably with the abutting contacting planar surface interface maintained by attachment mechanism such as bolts 48, preferably with the frame 42 adapted to be bolted down to the bridge structure 22 such as with the shown bolt holes. Preferably the natural resonant frequency 58 is tunable below 1.5 Hz. Preferably the natural resonant frequency 58 is lowerable with additional weights 62 received and added to the tuning mass 50. Preferably the tuning mass 50 has a tuning mass amount ≧90 lbs. Preferably the tuning mass 50 has a tuning mass amount ≧100 lbs. As shown in FIG. 2, 4, 5, 6, 10 tuning mass preferably is comprised of tuning mass weight plate members 62. As shown in the preferred embodiments in the FIG. the tuning mass weight plate members 62 are 15 lb weight plates. Preferably the natural resonant frequency 58 is lowerable with the movement of the tuning mass weight plate members 62 further out on the pivotal arm 64 and away from the pivotal axis 52. Preferably the tuning mass pivotal arm 64 has a longitudinal channel with the tuning mass weight plate members 62 movably positional along the longitudinal length of arm 64 and secured along the length of the arm such as with bolts. Preferably the spring 54 is comprised of at least three elastomeric torsional spring member 55 in series, with elastomer 56 sandwiched between rigid plates 57, with adjacent plates 57 attached together to work in series. Preferably the torsional springs 54 are comprised of at least three elastomeric torsional spring members 55 in series. Preferably the elastomeric torsional spring members 55 are comprised of an elastomer 56. As shown in FIG. 3, 4, 6, 7, 11, 12, 14, three elastomeric torsional spring members 55 are preferably utilized in series. As shown in FIG. 8-9 the elastomeric torsional spring members 55 are preferably comprised of a center elastomer 56 bonded between two rigid plate members 57. The elastomeric torsional spring members 55 are preferably utilized in series by fixing the adjacent rigid plate members of three spring members together, preferably such as shown in FIGS. 3, 4, 6, 7, 11, 12, and 14. The in series elastomeric torsional spring members 55 work in series between the support frame 42 and the tuning mass 50.

The invention includes a method of making a vibration absorber for a structure having a problematic excited frequency. The method includes providing a pivoting vibration absorber planar support frame plate, the pivoting vibration absorber planar support frame plate for attachment to the structure. The method includes providing a tuning mass and pivotally connecting the tuning mass to the pivoting vibration absorber planar support frame plate for pivotal movement relative to a pivotal axis. The method includes providing a torsional spring and disposing the torsional spring along the pivotal axis between the support frame and the tuning mass, the torsional spring providing a spring force responsive to a pivotal rotation of the tuning mass about the pivotal axis relative to the support frame wherein the pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs the excited frequency.

The method of making the bridge pivoting vibration absorber for a nonsuspension bridge elevated structure 22 having a problematic excited bridge frequency 24 below 1.5 Hz includes providing a pivoting vibration absorber planar support frame plate 42, the pivoting vibration absorber planar support frame plate 42 for attachment to the structure 22. The method includes providing a tuning mass 50 and pivotally connecting the tuning mass 50 to the pivoting vibration absorber planar support frame plate 42 for pivotal movement relative to a pivotal axis 52. The method includes providing a torsional spring 54 and disposing the torsional spring 54 along the pivotal axis 52 between the support frame 42 and the tuning mass 50, with the torsional spring 54 providing a spring force responsive to a pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame 42 wherein the pivoting vibration absorber has a natural resonant frequency 58 below 1.5 Hz which absorbs the excited frequency 24.

The invention includes a tuned vibration absorber for absorbing vibratory disturbances in a structure, the tuned vibration absorber including a vibration absorber planar support frame plate for attachment to the structure. The tuned vibration absorber includes a tuning mass movably connected to the support frame plate for movement relative to a pivotal axis. The tuning mass preferably includes an arm and an adjustment mass located along the length of the arm with the tuning mass suspended away from the planar support frame plate. The tuned vibration absorber includes a torsional spring located along the pivotal axis and positioned between the adjustment mass and the support frame plate and wherein the torsional spring provides a spring force responsive to pivotal rotation of the tuning mass about the pivotal axis relative to the support frame plate.

The tuned vibration absorber, for absorbing vibratory disturbances 24 in a bridge structure 22 includes vibration absorber planar support frame plate 42, the pivoting vibration absorber planar support frame plate 42 for attachment to the structure 22. The tuned vibration absorber includes the tuning mass 50 movably connected to the support frame plate 42 for movement relative to pivotal axis 52. Preferably the tuning mass 50 includes arm 64 and an adjustment mass 62 located along the length of the arm 64 with the tuning mass 62 suspended away from the planar support frame plate 42. The vibration absorber includes a torsional spring 54 located along the pivotal axis 52 and positioned between the adjustment mass 62 and the support frame plate 42 and wherein the torsional spring 54 provides a spring force responsive to pivotal rotation of the tuning mass 50 about the pivotal axis 52 relative to the support frame plate 42.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. 

1. A bridge, said bridge comprised of a structure having at least one excited bridge frequency, said structure having a bottom plate, a top plate, forming a bridge interior conduit chamber, a first bridge pivoting vibration absorber disposed in said bridge interior conduit chamber, said first bridge pivoting vibration absorber including a first bridge pivoting vibration absorber planar support frame with a first bridge pivoting vibration absorber foundation planar plate surface, said first bridge pivoting vibration absorber foundation planar plate surface abutting said top plate, said first bridge pivoting vibration absorber planar support frame attached to said top plate, a tuning mass pivotally connected to said first bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said first bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency, a second bridge pivoting vibration absorber disposed in said bridge interior conduit chamber, said second bridge pivoting vibration absorber including a second bridge pivoting vibration absorber planar support frame with a second bridge pivoting vibration absorber foundation planar plate surface, said second bridge pivoting vibration absorber foundation planar plate surface abutting said bottom plate, said second bridge pivoting vibration absorber planar support frame attached to said bottom plate, a tuning mass pivotally connected to said second bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said second bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency.
 2. A bridge as claimed in claim 1, said bridge including a third bridge vibration absorber disposed in said bridge interior conduit chamber, said third bridge vibration absorber including a third bridge vibration absorber planar support frame with a third bridge vibration absorber foundation planar plate surface, said third bridge vibration absorber foundation planar plate surface abutting said top plate, said third bridge vibration absorber planar support frame attached to said top plate, a tuning mass pivotally connected to said third bridge vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said third bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency.
 3. A bridge as claimed in claim 2, said bridge including a fourth bridge vibration absorber disposed in said bridge interior conduit chamber, said fourth bridge vibration absorber including a fourth bridge vibration absorber planar support frame with a fourth bridge vibration absorber foundation planar plate surface, said fourth bridge vibration absorber foundation planar plate surface abutting said bottom plate, said fourth bridge pivoting absorber planar support frame attached to said bottom plate, a tuning mass pivotally connected to said fourth bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said fourth bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency.
 4. A method of controlling vibrations in a bridge having an excited bridge frequency, said method comprised of the steps of: providing a first bridge vibration absorber, said first bridge vibration absorber including a first bridge vibration absorber planar support frame, a tuning mass connected to said first bridge vibration absorber planar support frame for movement relative to a axis, a spring disposed along said axis and between said support frame and said tuning mass, said spring providing a spring force responsive to a movement of said tuning mass about said axis relative to said support frame wherein said first bridge vibration absorber has a natural resonant frequency below 1.5 Hz, attaching said first bridge vibration absorber planar support frame to said bridge, wherein said first bridge vibration absorber natural resonant frequency absorbs said excited bridge frequency.
 5. A method as claimed in claim 4, said method including providing a second bridge vibration absorber, said second bridge vibration absorber including a second bridge vibration absorber planar support frame, a tuning mass connected to said second bridge vibration absorber planar support frame for movement relative to a axis, a spring disposed along said axis and between said support frame and said tuning mass, said spring providing a spring force responsive to a movement of said tuning mass about said axis relative to said support frame wherein said second bridge vibration absorber has a natural resonant frequency below 1.5 Hz, attaching said second bridge vibration absorber planar support frame to said bridge at a second placement point, said second placement point distal from said first bridge vibration absorber, wherein said second bridge vibration absorber natural resonant frequency absorbs said excited bridge frequency.
 6. A method as claimed in claim 4, said method including providing a third bridge vibration absorber, said third bridge vibration absorber including a third bridge vibration absorber planar support frame with a third bridge vibration absorber foundation planar plate surface, a tuning mass pivotally connected to said third bridge vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said third bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency, and attaching said third bridge vibration absorber to said bridge at a third placement point.
 7. A method as claimed in claim 4, said method including providing a fourth bridge vibration absorber, said fourth bridge vibration absorber including a fourth bridge vibration absorber planar support frame with a fourth bridge vibration absorber foundation planar plate surface, a tuning mass pivotally connected to said fourth bridge pivoting vibration absorber planar support frame for pivotal movement relative to a pivotal axis, a torsional spring disposed along said pivotal axis between said support frame and said tuning mass, said torsional spring provides a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said fourth bridge pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs an excited bridge frequency, and attaching said fourth bridge vibration absorber to said bridge at a fourth placement point.
 8. A bridge vibration absorber for absorbing a problematic excited bridge frequency of a bridge, said bridge vibration absorber comprised of a bridge vibration absorber planar support frame, a tuning mass connected to said bridge vibration absorber planar support frame for movement relative to a axis, a spring disposed along said axis and between said support frame and said tuning mass, said spring providing a spring force responsive to a movement of said tuning mass about said axis relative to said support frame wherein said bridge vibration absorber planar support frame provides for attachment of said bridge vibration absorber to said bridge with said bridge vibration absorber having a natural resonant frequency below 1.5 Hz.
 9. A method of making a vibration absorber for a structure having a problematic excited frequency, said method including: providing a pivoting vibration absorber planar support frame plate, said pivoting vibration absorber planar support frame plate for attachment to said structure, providing a tuning mass and pivotally connecting said tuning mass to said pivoting vibration absorber planar support frame plate for pivotal movement relative to a pivotal axis, providing a torsional spring and disposing said torsional spring along said pivotal axis between said support frame and said tuning mass, said torsional spring providing a spring force responsive to a pivotal rotation of said tuning mass about said pivotal axis relative to said support frame wherein said pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs said excited frequency.
 10. A tuned vibration absorber, for absorbing vibratory disturbances in a structure, said tuned vibration absorber comprising: a vibration absorber planar support frame plate, said pivoting vibration absorber planar support frame plate for attachment to said structure; a tuning mass movably connected to the support frame plate for movement relative to a pivotal axis, the tuning mass further comprising an arm and an adjustment mass located along the length of the arm with the tuning mass suspended away from the planar support frame plate; and a torsional spring located along the pivotal axis and positioned between the adjustment mass and the support frame plate and wherein said torsional spring provides a spring force responsive to pivotal rotation of the tuning mass about the pivotal axis relative to the support frame plate.
 11. A method of making a vibration absorber for a structure having a problematic excited frequency, said method including: providing a pivoting vibration absorber support frame, said pivoting vibration absorber support frame for attachment to said structure, providing a tuning mass arm and pivotally connecting said tuning mass arm to said pivoting vibration absorber support frame for pivotal movement relative to a pivotal axis, providing a first torsional spring member and at least a second torsional spring member and disposing said first torsional spring member and said second torsional spring member in series along said pivotal axis between said support frame and said tuning mass arm, said first torsional spring member and said at least second torsional spring member in series providing a torsional spring force responsive to a pivotal rotation of said tuning mass arm about said pivotal axis relative to said support frame wherein said pivoting vibration absorber has a natural resonant frequency below 1.5 Hz which absorbs said excited frequency. 